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Difference Between Chemical Reaction and Physical Reaction

Main Difference

The main difference between Chemical Reaction and Physical Reaction is that Chemical Reaction is the type of reaction that causes the chemical transformation of the reactants, whereas Physical Reaction is the reaction that causes the molecular rearrangement of the reactants to produce a physical change.

Chemical Reaction vs. Physical Reaction

A chemical reaction is the type of reaction that causes the change in the internal structure of the substance such that the formation of a new substance takes place, e.g., burning of paper or wood, etc. On the other side, the physical reaction is the type of reaction that causes the change in the physical features of the substance without disturbing their internal structure, e.g., freezing or melting of water.

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So, a chemical reaction is a reaction that causes a change in the composition and chemical properties of the reactant. On the other hand, the physical reaction causes a change in the physical properties of the reactant, e.g., color, shape, and size, etc. Thus, a chemical reaction causes the formation of a new product, whereas there is no new product formed during a physical reaction.

A chemical reaction is a type of irreversible reaction, i.e., the original matter cannot recover after the reaction. On the flip side, the physical reaction is a type of reversible reaction, i.e., the original matter can recover after the reaction. Moreover, energy absorbed or evolved during a chemical reaction. On the other side, there is no absorption and evolution of energy during a physical reaction.

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Comparison Chart

Chemical ReactionPhysical Reaction
A type of reaction that causes the change in the internal structure of the substance is known as a chemical reaction.A type of reaction that causes the change in the physical features of the substance without disturbing their internal structure is known as a physical reaction.
Change in Properties
It causes a change in the chemical properties and composition of the reactant.The physical reaction causes the change in the physical properties of the reactant, e.g., color, shape, and size, etc.
Type of Reaction
A chemical reaction is a type of irreversible reaction.The physical reaction is a type of reversible reaction.
Original Matter
During a chemical reaction, the original matter cannot recover after the completion of the reaction.During the physical reaction, the original matter can recover after the completion of the reaction.
Formation of New Product
The chemical reaction causes the creation of a new product.There is no new product formed during a physical reaction.
Energy
Energy absorbed or evolved while a chemical reaction.During a physical reaction, there is no evolution and absorption of energy.
Use of Equation
Chemical reactions can express by using a chemical equation.The physical reaction cannot express by the equation.
Examples
Examples of a chemical reaction are rusting of iron, burning of paper or wood and setting of curd, etc.Examples of physical reactions are cutting off trees, freezing or melting of water, and tearing of paper, etc.
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What is Chemical Reaction?

A chemical reaction is a type of reaction that causes the chemical transformation of the reactants. Alchemists, first of all, studied chemical transformations in the middle ages. They tried to convert the lead into gold by using lead-copper alloys and lead with sulfur.

During a chemical reaction, two or more reactants combined to make a different or new product. In this type of reaction, bonds between the atoms of the reactants broken down to get them to rearrange to form new compounds. This new product that has obtained after the completion of the reaction cannot be converted into reactants again so, it is known as an irreversible reaction.

During a chemical reaction, a chemical change takes place that changes the chemical properties of the substance and transforms it into a different substance that has different chemical compositions. Some signs of chemical change are an evolution of energy, change in odor, the formation of bubbles, and change in temperature, etc.

Moreover, it also involves the absorption and evolution of energy. It requires specific conditions to start a chemical reaction. Mostly, the rate of a reaction increases with the increase in temperature. It provides more thermal energy to reach the activation energy of the reaction, which is essential to break bonds between the atoms.

A chemical reaction can express in the form of an equation that is called a chemical equation. This chemical equation nominal or symbolic represents the starting compounds or reactants, end products, and reaction situation of the chemical reaction. Sometimes it also represents the intermediate products of the reaction.

Examples

Fireworks, rotting banana, fermentation of grapes, burning of paper or wood, the addition of vinegar into baking soda, bleaching a stain, etc. all are chemical reactions examples. Ones these reactions have completed, they cannot be converted into reactants again.

What is Physical Reaction?

The physical reaction is a type of reaction that causes the molecular rearrangement of the reactants to produce a physical change. These changes are affecting the form of a chemical compound but do not change its chemical composition. So, it only involves the change in physical properties of the reactant, i.e., change of strength, changes to crystal form, change of durability, textural change, size, color, shape, volume, and density, etc.

So, any change in color, shape, or odor represents a physical change. There is no new product formed during a physical reaction. It does not involve any evolution and absorption of energy. Moreover, these types of changes are reversible, i.e., the product can be changed back into the reactants. It cannot express in the form of the equation.

Examples

Molding of clay in a new shape, boiling of water, melting of butter on a warm toast, crumpling of paper, freezing of a juice box in the freezer, Melting of wax, dissolving sugar in water, chopping wood, etc. are the examples of physical reactions. All these changes are reversible, i.e., the reactant can be achieved again.

Key Differences

  1. A type of reaction that causes the change in the internal structure of the substance is known as chemical reaction whereas, a type of reaction that causes the change in the physical features of the substance without disturbing their internal structure known as a physical reaction.
  2. The chemical reaction causes a change in the composition and chemical properties of the reactant. On the other hand, the physical reaction causes a change in the physical properties of the reactant, e.g., color, shape, and size, etc.
  3. A chemical reaction is a type of irreversible or unchangeable reaction. Conversely, the physical reaction is a type of reversible reaction.
  4. During a chemical reaction, the original matter cannot recover after the completion of the reaction. On the flip side, in a physical reaction, the original matter can be recovered after the completion of the reaction.
  5. The chemical reaction causes the formation of a new product. On the other hand, there is no formation of a new product during a physical reaction.
  6. Chemical reactions can express by using an equation that is known as a chemical equation, whereas; the equation cannot express the physical reaction.
  7. The chemical reaction causes the evolution or absorption of energy. On the flip side, there is no evolution and absorption of energy during a physical reaction.
  8. Examples of a chemical reaction are rusting of iron, burning of paper or wood and setting of curd, etc. while the examples of physical reaction are cutting off trees, freezing or melting of water, and tearing of paper, etc.

Comparison Video

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Conclusion

The above discussion summarizes that chemical reaction and physical reaction are the two types of reactions. A chemical reaction is a type of irreversible reaction that causes the formation of a new product by changing the chemical properties of the reactants. On the other side, the physical reaction is a type of reversible reaction that causes a change in the physical properties of reactants.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss